/**
 * Copyright 2010-present Facebook.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.facebook.model;

import android.annotation.SuppressLint;
import org.json.JSONException;
import org.json.JSONObject;

import java.util.*;

class JsonUtil
{
  static void jsonObjectClear(JSONObject jsonObject)
  {
    @SuppressWarnings("unchecked")
    Iterator<String> keys = (Iterator<String>) jsonObject.keys();
    while (keys.hasNext())
    {
      keys.next();
      keys.remove();
    }
  }

  static boolean jsonObjectContainsValue(JSONObject jsonObject, Object value)
  {
    @SuppressWarnings("unchecked")
    Iterator<String> keys = (Iterator<String>) jsonObject.keys();
    while (keys.hasNext())
    {
      Object thisValue = jsonObject.opt(keys.next());
      if (thisValue != null && thisValue.equals(value))
      {
        return true;
      }
    }
    return false;
  }

  private final static class JSONObjectEntry implements Map.Entry<String, Object>
  {
    private final String key;
    private final Object value;

    JSONObjectEntry(String key, Object value)
    {
      this.key = key;
      this.value = value;
    }

    @SuppressLint("FieldGetter")
    @Override
    public String getKey()
    {
      return this.key;
    }

    @Override
    public Object getValue()
    {
      return this.value;
    }

    @Override
    public Object setValue(Object object)
    {
      throw new UnsupportedOperationException("JSONObjectEntry is immutable");
    }

  }

  static Set<Map.Entry<String, Object>> jsonObjectEntrySet(JSONObject jsonObject)
  {
    HashSet<Map.Entry<String, Object>> result = new HashSet<Map.Entry<String, Object>>();

    @SuppressWarnings("unchecked")
    Iterator<String> keys = (Iterator<String>) jsonObject.keys();
    while (keys.hasNext())
    {
      String key = keys.next();
      Object value = jsonObject.opt(key);
      result.add(new JSONObjectEntry(key, value));
    }

    return result;
  }

  static Set<String> jsonObjectKeySet(JSONObject jsonObject)
  {
    HashSet<String> result = new HashSet<String>();

    @SuppressWarnings("unchecked")
    Iterator<String> keys = (Iterator<String>) jsonObject.keys();
    while (keys.hasNext())
    {
      result.add(keys.next());
    }

    return result;
  }

  static void jsonObjectPutAll(JSONObject jsonObject, Map<String, Object> map)
  {
    Set<Map.Entry<String, Object>> entrySet = map.entrySet();
    for (Map.Entry<String, Object> entry : entrySet)
    {
      try
      {
        jsonObject.putOpt(entry.getKey(), entry.getValue());
      }
      catch (JSONException e)
      {
        throw new IllegalArgumentException(e);
      }
    }
  }

  static Collection<Object> jsonObjectValues(JSONObject jsonObject)
  {
    ArrayList<Object> result = new ArrayList<Object>();

    @SuppressWarnings("unchecked")
    Iterator<String> keys = (Iterator<String>) jsonObject.keys();
    while (keys.hasNext())
    {
      result.add(jsonObject.opt(keys.next()));
    }

    return result;
  }
}
